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Due to their ability to capture attention, emotional stimuli tend to benefit from enhanced perceptual processing, which can be helpful when such stimuli are task-relevant but hindering when they are task-irrelevant. Altered emotion-attention interactions have been associated with symptoms of affective disturbances, and emerging research focuses on improving emotion-attention interactions to prevent or treat affective disorders. In line with the Human Affectome Project's emphasis on linguistic components, we also analyzed the language used to describe attention-related aspects of emotion, and highlighted terms related to domains such as conscious awareness, motivational effects of attention, social attention, and emotion regulation. These terms were discussed within a broader review of available evidence regarding the neural correlates of (1) Emotion-Attention Interactions in Perception, (2) Emotion-Attention Interactions in Learning and Memory, (3) Individual Differences in Emotion-Attention Interactions, and (4) Training and Interventions to Optimize Emotion-Attention Interactions. This comprehensive approach enabled an integrative overview of the current knowledge regarding the mechanisms of emotion-attention interactions at multiple levels of analysis, and identification of emerging directions for future investigations.
Visual perception is a complex and dynamic process that plays a crucial role in how we perceive and interact with the world. The eyes move in a sequence of saccades and fixations, actively modulating perception by moving different parts of the visual world into focus. Eye movement behavior can therefore offer rich insights into the underlying cognitive mechanisms and decision processes. Computational models in combination with a rigorous statistical framework are critical for advancing our understanding in this field, facilitating the testing of theory-driven predictions and accounting for observed data. In this thesis, I investigate eye movement behavior through the development of two mechanistic, generative, and theory-driven models. The first model is based on experimental research regarding the distribution of attention, particularly around the time of a saccade, and explains statistical characteristics of scan paths. The second model implements a self-avoiding random walk within a confining potential to represent the microscopic fixational drift, which is present even while the eye is at rest, and investigates the relationship to microsaccades. Both models are implemented in a likelihood-based framework, which supports the use of data assimilation methods to perform Bayesian parameter inference at the level of individual participants, analyses of the marginal posteriors of the interpretable parameters, model comparisons, and posterior predictive checks. The application of these methods enables a thorough investigation of individual variability in the space of parameters. Results show that dynamical modeling and the data assimilation framework are highly suitable for eye movement research and, more generally, for cognitive modeling.
The interplay between cognitive and oculomotor processes during reading can be explored when the spatial layout of text deviates from the typical display. In this study, we investigate various eye-movement measures during reading of text with experimentally manipulated layout (word-wise and letter-wise mirrored-reversed text as well as inverted and scrambled text). While typical findings (e.g., longer mean fixation times, shorter mean saccades lengths) in reading manipulated texts compared to normal texts were reported in earlier work, little is known about changes of oculomotor targeting observed in within-word landing positions under the above text layouts. Here we carry out precise analyses of landing positions and find substantial changes in the so-called launch-site effect in addition to the expected overall slow-down of reading performance. Specifically, during reading of our manipulated text conditions with reversed letter order (against overall reading direction), we find a reduced launch-site effect, while in all other manipulated text conditions, we observe an increased launch-site effect. Our results clearly indicate that the oculomotor system is highly adaptive when confronted with unusual reading conditions.
Previous research on the interplay between static manual postures and visual attention revealed enhanced visual selection near the hands (near-hand effect). During active movements there is also superior visual performance when moving toward compared to away from the stimulus (direction effect). The "modulated visual pathways" hypothesis argues that differential involvement of magno- and parvocellular visual processing streams causes the near-hand effect. The key finding supporting this hypothesis is an increase in temporal and a reduction in spatial processing in near-hand space (Gozli et al., 2012). Since this hypothesis has, so far, only been tested with static hand postures, we provide a conceptual replication of Gozli et al.'s (2012) result with moving hands, thus also probing the generality of the direction effect. Participants performed temporal or spatial gap discriminations while their right hand was moving below the display. In contrast to Gozli et al (2012), temporal gap discrimination was superior at intermediate and not near hand proximity. In spatial gap discrimination, a direction effect without hand proximity effect suggests that pragmatic attentional maps overshadowed temporal/spatial processing biases for far/near-hand space.
Coupling of attention and saccades when viewing scenes with central and peripheral degradation
(2016)
Degrading real-world scenes in the central or the peripheral visual field yields a characteristic pattern: Mean saccade amplitudes increase with central and decrease with peripheral degradation. Does this pattern reflect corresponding modulations of selective attention? If so, the observed saccade amplitude pattern should reflect more focused attention in the central region with peripheral degradation and an attentional bias toward the periphery with central degradation. To investigate this hypothesis, we measured the detectability of peripheral (Experiment 1) or central targets (Experiment 2) during scene viewing when low or high spatial frequencies were gaze-contingently filtered in the central or the peripheral visual field. Relative to an unfiltered control condition, peripheral filtering induced a decrease of the detection probability for peripheral but not for central targets (tunnel vision). Central filtering decreased the detectability of central but not of peripheral targets. Additional post hoc analyses are compatible with the interpretation that saccade amplitudes and direction are computed in partial independence. Our experimental results indicate that task-induced modulations of saccade amplitudes reflect attentional modulations.
Cognitive psychology is traditionally interested in the interaction of perception, cognition, and behavioral control. Investigating eye movements in reading constitutes a field of research in which the processes and interactions of these subsystems can be studied in a well-defined environment. Thereby, the following questions are pursued: How much information is visually perceived during a fixation, how is processing achieved and temporally coordinated from visual letter encoding to final sentence comprehension, and how do such processes reflect on behavior such as the control of the eyes’ movements during reading. Various theoretical models have been proposed to account for the specific eye-movement behavior in reading (for a review see Reichle, Rayner, & Pollatsek, 2003). Some models are based on the idea of shifting attention serially from one word to the next within the sentence whereas others propose distributed attention allocating processing resources to more than one word at a time. As attention is assumed to drive word recognition processes one major difference between these models is that word processing must either occur in strict serial order, or that word processing is achieved in parallel. In spite of this crucial difference in the time course of word processing, both model classes perform well on explaining many of the benchmark effects in reading. In fact, there seems to be not much empirical evidence that challenges the models to a point at which their basic assumptions could be falsified. One issue often perceived as being decisive in the debate on serial and parallel word processing is how not-yet-fixated words to the right of fixation affect eye movements. Specifically, evidence is discussed as to what spatial extent such parafoveal words are previewed and how this influences current and subsequent word processing. Four experiments investigated parafoveal processing close to the spatial limits of the perceptual span. The present work aims to go beyond mere existence proofs of previewing words at such spatial distances. Introducing a manipulation that dissociates the sources of long-range preview effects, benefits and costs of parafoveal processing can be investigated in a single analysis and the differing impact is tracked across a three-word target region. In addition, the same manipulation evaluates the role of oculomotor error as the cause of non-local distributed effects. In this respect, the results contribute to a better understanding of the time course of word processing inside the perceptual span and attention allocation during reading.
Nikotin in den unterschiedlichsten Darreichungsformen verringert bei verschiedenen Spezies im räumlichen Hinweisreizparadigma die Kosten invalider Hinweisreize. Welcher Teilprozess genau durch Nikotin beeinflusst wird, ist bislang nicht untersucht worden. Die gängige Interpretation ist, daß Nikotin das Loslösen von Aufmerksamkeit von einem bisher beachteten Ort erleichtert. In fünf Studien, drei elektrophysiologischen und zwei behavioralen wurden drei mögliche Mechanismen der Nikotinwirkung an Nichtrauchern untersucht. Experiment 1 und 2 gingen der Frage nach, ob Nikotin eine Modulation sensorischer gain Kontrolle bewirkt. Dazu wurden ereigniskorrelierte Potentiale (EKP) im Posner-Paradigma erhoben und die Wirkung von Nikotin auf die aufmerksamkeitsassoziierten Komponenten P1 und N1 betrachtet. Nikotin verringerte die Kosten invalider Hinweisreize bei Aufmerksamkeitslenkung durch endogene Hinweisreize, nicht aber bei exogenen Hinweisreizen. Die P1 und N1 Komponenten zeigten sich unbeeinflusst von Nikotin, damit findet also die Annahme einer Wirkung auf sensorische Suppression keine Unterstützung. In Experiment 3 und 4 wurde untersucht, ob Nikotin einen Effekt auf kostenträchtige unwillkürliche Aufmerksamkeitsverschiebungen, Distraktionen, hat. In Experiment 3 wurden in einem räumlichen Daueraufmerksamkeitsparadigma Distraktionen durch deviante Stimulusmerkmale ausgelöst und die Wirkung von Nikotin auf eine distraktionsassoziierte Komponente des EKP, die P3a, betrachtet. In Experiment 4 wurde in einem Hinweisreizparadigma durch zusätzliche Stimuli eine Distraktion ausgelöst und die Nikotinwirkung auf die Reaktionszeitkosten untersucht. Nikotin zeigte keinen Einfluss auf Distraktionskosten in beiden Studien und auch keine Wirkung auf die P3a Komponente in Experiment 3. In Experiment 4 wurde zusätzlich die Wirkung von Nikotin auf das Loslösen von Aufmerksamkeit untersucht, indem die Schwierigkeit des Loslösens variiert wurde. Auch hier zeigte sich keine Nikotinwirkung. Allerdings konnte in beiden Studien weder die häufig berichtete generelle Reaktionszeitverkürzung noch die Verringerung der Kosten invalider Hinweisreize repliziert werden, so dass zum Einen keine Aussage über die Wirkung von Nikotin auf Distraktionen oder den Aufmerksamkeitsloslöseprozess gemacht werden können, zum Anderen sich die Frage stellte, unter welchen Bedingungen Nikotin einen differentiellen Effekt überhaupt zeigt. Im letzten Experiment wurde hierzu die Häufigkeit der Reaktionsanforderung einerseits und die zeitlichen Aspekte der Aufmerksamkeitslenkung andererseits variiert und der Effekt des Nikotins auf den Validitätseffekt, die Reaktionszeitdifferenz zwischen valide und invalide vorhergesagten Zielreizen, betrachtet. Nikotin verringerte bei Individuen, bei denen Aufmerksamkeitslenkung in allen Bedingungen evident war, in der Tendenz den Validitätseffekt in der ereignisärmsten Bedingung, wenn nur selten willentliche Aufmerksamkeitsausrichtung notwendig war. Dies könnte als Hinweis gedeutet werden, dass Nikotin unter Bedingungen, die große Anforderungen an die Vigilanz stellen, die top-down Zuweisung von Aufmerksamkeitsressourcen unterstützt.